In this stage, you select the Integration for which the policy is created. In this case, Slack integration must be selected.

1. Click Policies from the left menu.

2. Click + New Policy.

3. Select Sensitive Data.

4. Select the Slack integration.

This document explains how to set up the Policy Scope for Slack Pro and Slack Business+ editions. If you are using a Slack Enterprise edition, you must refer to this document.

The Scope stage allows you to select Slack Channels and Connections which must be scanned by the policy.

To configure Policy Scope:

1. Select one of the following options under the Select Channels section. The scope of this policy is limited to only those channels and connections which you select in this section.

• Channels: Select the Select All check box to scan the data in all your Slack channels. Select the Public Channels check box to scan data only in your Public Slack Channels. Select the Private Channels check box to scan data only in your private Slack channels.

• Connections: Select the Select All check box to scan the data in all your Slack connections. Select the Public Connect Channels check box to scan data only in your Public connect Slack Channels. Select the Private Connect Channels check box to scan data only in your private connect Slack channels.

Applying Filters

The Filters section provides you an added level of granularity in setting the Scope. You can use specific filters to filter data based on Users, Groups, Channels, or Apps.

How Slack Filters Work

Slack policies support filtering based on users, user groups, and apps. These options provide flexible, granular control on whom to apply the monitoring. The Only Include option is very useful to pick specific required users, groups or apps for monitoring. particularly useful for creating broad policies with specific exceptions. Combining user and group options allows for complex, layered access control. The exclude option allows you to exclude the monitoring of unwanted users, user groups and apps, thus reducing the unwanted noise from secure entities.

Filtering by Users

• Only Include: Only messages sent by selected users are scanned for sensitive data.

• Exclude: Messages sent by excluded users are not scanned.

Filtering by Groups

• Only Include: Only messages sent by users in included Slack groups are scanned for sensitive data.

• Exclude: Messages sent by users in excluded Slack groups are not scanned.

Filtering by Apps

• Only Include: Only messages sent by included Slack apps are scanned for sensitive data.

• Exclude: Messages sent by excluded Slack apps are not scanned.

Priority Order for Conflict Management

Nightfall uses prioritization to decide which messages to scan when multiple filters are configured in a policy. The order of priority is:

1. User Exclusion

2. User Inclusion

3. Group Exclusion

4. Group Inclusion

How it works:

1. Initially, Nightfall checks if the file owner is on the User Exclusion list. If they are, their messages are not scanned, no matter how other filters are configured in a policy.

2. If the user isn't excluded, Nightfall then checks if they're on the User Inclusion list. If they are, all their messages are scanned for that policy.

3. If the user isn't on either the exclusion or inclusion lists, Nightfall looks at group memberships. It checks if the user belongs to any excluded groups. If they do, their messages are not scanned for that policy.

4. Finally, if none of the above apply, Nightfall checks if the user is in any included groups. If they are, their messages are scanned for that policy. If not, the messages are not scanned.

DLP policies are a set of rules that include specific conditions, actions, and exceptions that monitor and filter data. DLP policies help you to monitor and remediate the flow of sensitive data within your organization. Depending on your Nightfall policy configuration, you can set up policies to monitor data that is sent through some or all applications within your organization. You can configure policies and choose to not apply them all the time.

Before you define a policy, or a set of policies, you must define the objectives of each policy, which can then be fulfilled when you configure the policy. Here are a few important questions to ask before configuring your policies:

• What data do you plan to monitor?

• Where within the organization do you want to monitor?

• What should be the scope of each policy?

• What conditions must apply for the policy to match?

• What exceptions/exclusions can be allowed?

• What remediation actions should the policy take?

You can now set up policies to determine which Slack channels are monitored (and which are excluded) for violations and what actions Nightfall must take. Policies determine the content that will be scanned by Nightfall, and workflows that are followed to manage violations.

Policies for Slack integration allow you to define configurations specific to Slack, such as how to handle messages for particular channels or use automated actions such as Quarantine.

Creating a Nightfall policy involves the following tasks:

1. Create Policies

2. Define the policy scope and exclusions

3. Configure Detection Rule

4. Configure Automated Actions

Note: Instructions to configure policies differ for Slack Pro and Slack Enterprise options. Refer to the Slack tier that you are using.

This stage allows you to select notification channels if a policy violation occurs. The notification alerts are sent at two levels.

Admin Alerting

The steps to configure alert channels for policy-level integration are the same as in the case of integration-level alerts. You can refer to this document for steps.

End-User Notification

This section allows you to configure notifications to be sent to the end user whose actions triggered the violation.

Custom Message

Enter a custom message to be sent to the end user. This message is sent in an Email. You can modify the default message provided by Nightfall and draft your message. The total character length allowed is 1000 characters. You can also add hyperlinks in the custom message. The syntax is <link | text >. For example, to hyperlink https://www.nightfall.ai with the text Nightfall website, you must write <https://www.nightfall.ai | Nightfall website> .

Automation

You can select one of the following methods. You must turn the toggle switch to use this option.

• Via Email: This option sends an Email to the End user.

• Via Slack: This option sends a Slack notification to the end-user in a pre-configured channel.

End-User Remediation

End-user remediation (also known as Human Firewall) allows you to configure remediation measures that end users can take, when a violation is detected on their GitHub operations. You must turn on the toggle switch to use this option. The various available options are as follows.

• Delete: This option allows the end-user to delete the message that caused the violation.

• Report as False Positive with Business Justification: This option allows end users to report false positive alerts and provide a business justification as to why the alert is considered to be false positive.

• Report as False Positive: This option allows end users to report false positive alerts.

• When a Violation is Reported as False Positive: You can use this option to set actions to be taken when a violation is reported as false positive by the end-user. You can either set the remediation to be automatic or manual.

• Remind Every (until Violation expires): You can use this option to set a reminder for the end-user to take action on the violation. You can choose to remind the end user every 24, 48, or 72 hours.

In this final stage, you assign a name to the policy, verify your configurations, and create the policy.

1. Enter a name for the policy.

2. (Optional) Enter a description for the policy.

3. Choose the Policy risk score. By default the risk score is set to Nightfall Risk Score. You can set it to Custom Risk score, and select one of the risk levels, if required. To learn more about Risk scoring, refer to the #risk-scoring document.

1. Click Next.

2. Verify if all the policy configurations are set up as per your requirements.

3. (Optional) Click back to modify any of the policy configurations.

4. Click Submit.

In this section, you can select the Detection rules for the policy and If not already created, you can create detection rules. To learn more about how to configure detection rules, see Configuring Detection Rules.

To select detection rules, select the detection rules from the list of rules that display.

You can also sort the rules that you want to view.

• All Detection Rules: View all detection rules created

• Selected Detection Rules: View detection rules that are selected and mapped to this policy

• Unselected Detection Rules: View detection rules that are neither selected nor mapped to this policy.

1. Click Next.

This section describes the various actions that Nightfall takes automatically when a violation is detected. You must turn on the toggle switch to enable an action. You can also set the timeline as to when an action must be taken (immediately after detecting a violation or after some time).

Currently, Nightfall supports the Delete automated action for the Slack Pro and Business+ editions.

You must first turn on the toggle switch to enable any of the automated actions.

Once you enable the toggle switch, you can configure when the action must be applied.

If you select immediately, the action is implemented automatically after the sensitive data is detected.

If you select After, you must also set the time frame as to when exactly the action must be applied, after detecting the sensitive data.

The action is described as follows.

Delete

The delete action automatically deletes the message or attachment that has sensitive data. This is a permanent action and cannot be reverted.

When an end user violates a policy in Slack, an Event is generated based on the notification settings configured by you in the policy configurations. To learn more about Events, see Sensitive Data Protection Events.

This document explains where you can find notifications on Slack policy Events and what actions can be taken.

Nightfall Events

To view Events in the Nightfall Console:

1. Click Detection and Response from the left pane.

2. (Optional) Modify the days filter to view Events prior to last 7 days. By default the Events recorded in the Last 7 Days are displayed.

1. Apply filters to view only the Slack Events.

Once you filter the Events to view only the Slack Events, you can refer to the #event-list-view section to learn more about the available options.

1. Click on any of the Events to view details of an Event. You may click anywhere in the row of an Event that you wish to inspect. Details will be present via a side panel.

The side panel (or the Event detail view) is divided into three separate sections. The first section has information about the occurrence of individual findings with a preview. The third section is an activity log for the Event. Both these sections reveal information that is common across all sources/integrations. You can refer to these common sections in the #event-detail-view section.

The second section displays details that are source / integration specific and so the details vary from one integration to the other.

Event Actions

Nightfall allows you to take various action on Events. When you take an action on an Event, the status of the Event changes accordingly. To learn more about Event status, refer to the Event Status document.

In Slack, you can take actions either from the Event list view page or the Event detail view page. On the Event list view page, you can click the ellipsis menu to view the available list of actions.

On the Event detail view, you can view the applicable actions from the actions section at the bottom.

To view the complete list of actions, applicable to all the integrations, you can refer to the Applying Actions on Events document.

The list of actions supported for Slack are as follows. Some of these actions are common to other integrations as well.

• Copy Event Link: The action copies the link to the Event. You can save or send this link to directly open the Event. This action is available only on the Event detail view.

• View in Slack: This action redirects to the sensitive data in the source Slack account. While this action is available only on the Event detail view, please note that relevant access to the source of sensitive data in Slack should be present.

• Ignore: The ignore action flags Nightfall to ignore all the findings in the Event and may be taken if you find the findings false positive. This action marks the Event as resolved and moves it to the Resolved section. You can undo this action.

• Acknowledge: You can take this action to notify other users that you have looked into this Event and will take suitable action in future.

• Notify Email: This action notifies the end user who added the sensitive data file to the OneDrive about the event, through email.

• Notify Slack: This action notifies the end user who added the sensitive data file to the OneDrive about the event, through Slack.

• Send to JIRA: This action creates a JIRA ticket for the Event. You can pick a project and Issue type while creating the JIRA ticket and can assign the JIRA ticket to the end-user.

• Quarantine: This action quarantines the message with sensitive data. Click here to learn more about the action. This action is available only in the Slack Enterprise edition.

• Redact: This action redacts the sensitive data present in the Slack message. Click here to learn more about the action. This action is available only in the Slack Enterprise edition.

• Delete: This action deletes the sensitive data present in Slack messages or attachments.

• Resolve: This action must be taken when the sensitive data is removed completely. This action resolves the Event.

Email Notification

• When a data leak occurs, Slack sends an Email to end users, if they have configured Email as a Notification method in their Slack account.

• Additionally, if you have configured Email Notification in Admin Alerting, Nightfall admins receive the Email notification as shown in the following image.

• If you have configured Email Notification in the Automation section of End User Notification settings, end users receive an email from Nightfall. This Email allows end users to take actions from within the Email. The actions are present at the end of the email. The available actions depend on the settings configured by you admin in the End User Notification section.

Viewing Notifications in Slack

If you have configured Slack as a Notification in the Automation section of End User Notification, end users can view the violation notification from within Slack.